This invention relates in general to the production of curved fittings and deals more particularly with a machine that forms a curved conduit from a continuous strip of sheet metal or another sheet material.
Although machines have been proposed for producing straight conduits by spirally winding a strip of sheet material and joining the adjacent edges, such machines would not be capable of forming curved conduits or fittings such as pipe elbows and the like. In view of the widespread use of curved tapers, offsets, goose necks, elbows and other types of curved conduits and fittiings in the sheet metal industry and related fields, it is apparent that a need exists for a machine that is capable of economically manufacturing such parts from a continuous strip of sheet metal or a similar sheet material. The primary goal of the present invention is to meet that need.
More specifically, it is an object of this invention to provide a machine that operates to form, from a continuous strip of sheet material, spirally wound conduits which are curved in shape.
Another object of the invention is to provide a machine of the character described which is able to form conduits of various sizes, shapes, and curvatures. It is an important feature of the invention in this respect that conduits having compound bends may be produced, as may straight pipes, smoothly curved elbows, goose necks, off-sets, and fittings of virtually any other shape. Further, the machine is readily adjustable as to the diameter and curvature of the conduits that are formed.
Still another object of the invention is to provide, in a machine of the character described, cutting and bending rollers that effectively and reliably cut and form the strip in the desired shape.
A further object of the invention is to provide a machine of the character described that has a drive train which accurately controls the speed of the various operating components relative to one another, while at the same time providing for quick and easy adjustment of the speeds at which the components are driven.
An additional object of the invention is to provide, in a machine of the character described, an arrangement for effectively guiding and securely interlocking the edges of the spirally wound conduit.
In conjunction with the preceding object, it is yet another object of the invention to provide a machine of the character described wherein each side edge of the strip is progressively and gradually bent in a manner to avoid abrupt bends and other stresses which can weaken the sheet material.
A still further object of the invention is to provide a machine of the character described which is constructed simply and economically and which operates reliably with only minimal maintenance requirements.
Other and further objects of the invention, together with the features of novelty appurtenant thereto, will appear in the course of the following description.